It looked like the best fig year ever, with maybe 20 fruits forming on my potted tree as the season progressed. But frost is coming any day, and many of those figs are still hanging there, undersized and hard and green, destined never to achieve ripeness.
Why can’t I get this right?
The figgy frustrations of Northeastern gardeners like me are the subject of Lee Reich’s latest book, “Growing Figs in Cold Climates: A Complete Guide.” In it, he suggests various strategies for outsmarting Ficus carica, a subtropical plant that originated in the very different climate of the Middle East, but can be coaxed to grow and even fruit in much colder zones — with the right strategies.
You have probably read about or seen some of the traditional lengths that fig growers go to, like wrapping a tree with burlap stuffed with leaves, an adequate protection outside a Brooklyn brownstone, maybe, but not too much farther north.
Other gardeners prune in fall, after leaf drop, and then dig halfway around the fig’s rootball and bend the plant down to the opposite side, covering it with soil or leaves and a tarp. For maximum insulation, some dig a trench alongside the fig, and then lower the tree into the trench and cover it.
That’s a lot of work — “and it can look ugly, too, in the winter landscape,” said Mr. Reich, who knows from experience, as he tried that years ago.
We should all be so lucky (or smart?) as to have a simple greenhouse like the one Mr. Reich has on his 2.25-acre property in New Paltz, N.Y., a 20-by-20-foot, poly-covered structure that he keeps minimally heated so the temperature doesn’t drop below 37 degrees.
Four of his figs are planted in the greenhouse’s dirt floor, trained as espaliers. It’s not just a figgery in there, however. The greenhouse is also home to a diversity of edibles, including mache, lettuce, kale and even celery in winter, along with spring’s flower seedlings and summer cucumbers.
But the no-frills way to grow a fig — in places where the winters are cold — is in a pot. That’s provided you have the right spot to stash it when the freezes arrive, as Mr. Reich does in his barely heated basement, where he has 15 potted trees.
Mr. Reich has long grown not just figs, but also the likes of medlar and pawpaw, among the plants featured in “Uncommon Fruits Worthy of Attention,” his forward-thinking 1991 book that influenced gardeners to consider a wider palette. Even with more common choices like blueberries, Mr. Reich pushes the limit, harvesting 190 quarts a year, for example, from highbush plants grown inside “our bird-proof blueberry temple,” an outdoor structure clothed on the sides in one-inch mesh and covered with netting at ripening time up top, too.
Among tree fruits, figs are distinctive. Most commonly grown temperate-zone possibilities, like apples and pears, produce their fruit on older wood, the previous year’s and earlier. Some fig varieties can do that as well, delivering what is called a breba crop early, on last year’s stems. But those best suited to growing in colder climates, including familiar varieties like Brown Turkey and Chicago Hardy, produce their main crop — sometimes their only crop — on new shoots.
Keeping the fig tree scaled down to container-grown proportions by pruning does not eliminate the possibility of harvest. To the contrary, success with figs in colder zones, Mr. Reich stressed, requires some combination of two practices: proper pruning and adequate protection.
Fig in a Pot 101
Mr. Reich’s first fig lived in a 12-inch-diameter clay pot in his apartment, when he began graduate school in horticulture and soil science at the University of Wisconsin-Madison.
“I knew little about growing plants generally or figs successfully,” he recalled. “As you might guess, I never got a fig.”
A bigger pot is better, provided it can be maneuvered into its winter storage location. But whatever the size, a drainage hole is essential, as is a sunny spot for the plant to spend the outdoor growing season.
Although a fig would happily sink its roots into the earth, straight garden soil is not practical in containers, where it is too heavy and interferes with drainage. Mr. Reich, ever the soil scientist, custom-blends his own formula: equal parts of peat, perlite, compost and garden soil. To every five gallons of his recipe, he adds a quarter cup of limestone and half a cup of soybean meal (which provides supplemental nitrogen). Mix thoroughly, then screen before using.
The shortcut: Use standard bagged potting mix, with the occasional application of a water-soluble fertilizer, according to the label directions.
Attention to watering is key. With pots small enough to lift or at least tip, Mr. Reich recommends learning to gauge the weight after a thorough watering and then when the soil has started to dry. The difference in weight should offer a cue as to when you need to reapply.
“If you use a potting mix with good drainage, you don’t have to worry about overwatering,” said Mr. Reich, who has emitters from his automated drip-irrigation system positioned to deliver a brief watering twice a day to all of his potted figs.
For overwintering, figs require almost no water — just enough to prevent desiccation, perhaps once in late winter. And light is not required, as the figs will be leafless.
The ideal you’re trying to simulate, he said, is a Mediterranean winter, somewhere between freezing and the low 40s. “But figs can tolerate maybe 10 degrees and certainly 20,” he said, with those in larger pots having more root insulation and therefore a little extra hardiness.
“Don’t hurry the pots into winter storage, though,” Mr. Reich advised. His plants head into the cellar around mid-December, once they have gradually hardened off outside, in the increasing cold from October onward. Don’t rush their reawakening, either, with too much warmth or water; it’s best not to bring them back outside “until temperatures remain reliably in the high 20s.”
My insulated but unheated barn gets colder than Mr. Reich’s cellar, but I never get dieback on the figs, nor do they awaken too early and get zapped; that’s not my issue. Apparently, I need to get tougher with pruning, Mr. Reich said — both above and below the soil surface.
Pruning (Including Those Roots)
Most pruning of a fig is done when the plant is dormant, from late fall to early spring. And sometimes the decision as to when is a purely practical one. If the doorway to the storage spot is too narrow or the plant too heavy, you may want to prune before stashing it, and even unpot it to reduce weight, covering the unearthed rootball with a plastic bag.
As the main-season crop produced on new shoots is what we cold-climate gardeners will be focused on, the pruning plan encourages a well-spaced set of shoots, not too low on the plant. A fig reduced to ground level — whether by cold or a shears-wielding gardener — will usually send up new shoots from its roots. But there may not be time for the fig to recover sufficiently and then also set fruit on the fresh growth.
It turns out that I need to prune my fig to prompt more current-season fruit-bearing shoots. “That means lopping a few of the sturdiest stems back to about two feet above ground level,” Mr. Reich said. “And cutting most of the other, more spindly stems back all the way.”
Another piece of advice: Root pruning every year or two makes room to refresh the potting medium, so the plant does not exhaust its resources. When the fig comes out of storage, tip it out of its pot, onto a tarp, and do some trimming. With an 18-inch-wide rootball, Mr. Reich might slice off an inch and a half or two of roots all around, before repotting.
A Step-Over Espalier
Inspired by his greenhouse espaliers, Mr. Reich has been experimenting with an outdoor fig pruned as a horizontal cordon or step-over espalier: a fruit tree trained very low, to take advantage of the earth’s insulating power.
“It’s easy to cover,” Mr. Reich said. “And rather than bend it over every fall, it stays down.”
Before covering the young plant its first winter, he cut it down close to ground level. From the shoots that arose the next spring, he saved one to train horizontally, as the trunk.
Where space allows, a pair heading in opposite directions, or even four forming an X pattern, could be retained — all potentially striking ornamental garden elements that also serve as a framework for each season’s fruiting stems. To train the retained young shoots, tie them down to low stakes or weigh them down with rope secured to two bricks.
New shoots emanate in spring from the older wood of the cordon. Mr. Reich allowed one vertical shoot to develop every eight inches or so along the trunk, each a potential fruit-bearer. Because these shoots develop off the older wood of the horizontal trunk, they start growing earlier than if the plant had been cut back more severely, and may reach 10 feet or taller in a season.
That means the ripening of the main crop begins earlier, too — which, for cold-climate fig growers, is what success is all about.
Margaret Roach is the creator of the website and podcast A Way to Garden, and a book of the same name.
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